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Spitfire "79 Spitfire loss of power

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Dudly

Dudly

Jedi Hopeful
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"79 Spitfire loss of power

Hi All, it's been a while since I've posted, I've been trying to enjoy every nice day we've had round here. Plus I replaced my entire (nearly) cooling system.

Problem is every once in a while I'll be motoring along and out of the blue she seems to loose all power, just conk out.

Yesterday I was going about 50, it happened for about 1 sec, just coasted for that moment then we were back on line. It happened in the summer a few times just like that. I thought it was the coil so I replaced it, but I still had the same issue arise, as stated, on my drive yesterday. I have the electronic ignition with the Allison black box.

Any suggestions ?

Thanks,
Doug
 
Re: "79 Spitfire loss of power

Check the tach when it happens. If it drops instantly to zero it would indicate an ignition problem. I had to replace an ignition switch because of a similar symptom. Check all connections, especially grounds.
 
Re: "79 Spitfire loss of power

I had similer problems with my 7. I traced it to the multi pin plug under the dash. Particularily the ground (black) wire pin and socket.
 
Re: "79 Spitfire loss of power

It's the black box. Mine did it two summers ago and I swapped out the box from another car and it drove fine for a year. I developed a leak in the exhaust manifold this summer and had the car out out last week and it did it again, (quit running till it cooled down). These boxes come up on eBay from time to time. I think I may replace the ignition with something more reliable though.
Good luck!
 
Re: "79 Spitfire loss of power

I was wondering if it might be that Allison black box, perhaps it's giving up the farm. Guess it'll give me the excuse to buy the Protronix system. Also won't hurt to go through the connections and give them all a good once over with some steele wool.

Thanks guys.
 
Re: "79 Spitfire loss of power

Ok, question # 2. If I were to buy the Protronix kit. Will I be totally bypassing the Allison black box ? If so can I just unbolt it and toss it?
 
Re: "79 Spitfire loss of power

AFAIK the pertronix will bypass the Allison.

When I had that problem it was that the wire from the distrbutor to the coil was broken, where the wire flexes at the dirstributor. FWIW.

Those later Electronic ignitions are a real PITA, while I'm playing with the contractions.
 
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